Evaluation of Analytical and Numerical Methods for Buckling of Sandwich Beams Based on Experimental Results

This paper focuses on the evaluation of the analytical and numerical methods for buckling critical load calculation in sandwich composite beams with different slenderness ratios subjected to axial loads. The composite sandwich panel is made up of woven carbon/epoxy faces and a PVC foam core laminated in vacuum infusion process, widely used in maritime and aerospace industries. The benchmark buckling critical loads are obtained for fixed–fixed as well as hinged–hinged sandwich columns experimentally. Analytical methods include Allen’s thick faces version formulation, higher order sandwich panel theory (HSAPT) and extended high-order sandwich panel theory (EHSAPT). Numerical analyses are performed using linear and nonlinear finite element methods. The analytical and numerical predictions are in good agreement with the experimental results. It is shown that for this type of sandwich beams, the results of the general buckling critical load obtained by higher-order analytical methods do not have a significant advantage over Allen's simple formulation. Further, the nonlinear finite element analysis has the highest accuracy among all other methods.

Keywords:

Carbon/epoxy PVC core sandwich , Buckling test , Higher-order theory , Finite element analysis.